1. Field of the Invention
The present invention relates to a backlight module, and more particularly to a backlight module without a light guide plate.
2. Description of the Prior Art
With advantages of low radiation, low power consumption, light in weight, and thin in thickness, liquid crystal display devices are widely applied in electronic apparatuses such as personal digital assistants (PDA), notebook computers, digital cameras, and mobile phones. Since liquid crystal display panels are not self-emission, the liquid crystal display devices require backlight modules disposed below the liquid crystal display panels to provide surface light sources for displaying.
Refer to FIG. 1, FIG. 1 is a schematic diagram illustrating a backlight module 10 of the liquid crystal display device in the prior art. The backlight module 10 includes a frame 12, a reflection plate 14, a plurality of the light tube 16, a light guide plate 18, and a plurality of transparent optical thin films 20. A portion of light beam emitted from the light tube 16 directly enter the light guide plate 18, the remaining light beams are reflected on the surface of the reflection plate 14 and then enter the light guide plate 18. In addition, a plurality of transparent optical thin films 20 are disposed on an exiting plane of the light guide plate 18, so that the backlight module 10 can output more uniform light beams to provide the liquid crystal display device (not shown in the figure) with the light source for displaying images.
However, the light guide plate 18 in the backlight module 10 is usually made of plastic, and the light guide plate 18 has a definite weight. This is contrary to the development of the liquid crystal display device toward the weight reduction. As a result, how to reduce the weight of the backlight module for further decreasing the weight of the liquid crystal display device is a major issue required to be improved.